Polyurethane for Precision Lenses

Title: POLYURETHANE HAVING LOW VOLUME SHRINKAGE

Number/Link: US2013/116357

Applicant/Assignee: Bayer

Publication date: 9-05-2013 (priority PCT/DE)

“Gist”: Modified m-XDI mixtures are used to prepare solvent-free polyurethane or polythiourethane with high refractive index, low dispersion and low volume shrinkage.

Why it is interesting: Production of polyurethane and (esp.) polythiourethane for optical applications is well known. Usually araliphatic isocyanates are used, often together with mercapto-functional compounds resulting in materials with high refractive index, low dispersion and low discolouration. Bayer has found that by modifying araliphatic diisocyanates, e.g. m-xylenediisocyanate, by partial trimerization or by partly converting into allophanate or biuret (after adding some diol or water respectively) optical polyurethanes or polythiourethanes can be produced without the use of solvent and with less shrinkage. The materials are therefore more useful for precision optics.

1,3-bis(isocyanatomethyl)benzene (m-XDI)

Solid Polyurethane Electrolyte

Title: POLYURETHANE BASED MEMBRANES AND/OR SEPARATORS FOR ELECTROCHEMICAL CELLS

Number/Link: WO2013/062990

Applicant/Assignee: Lubrizol

Publication date: 2/05/2013

“Gist”: TPU prepared from a DEG-adipate polyester diol, HQEE and 4,4′-MDI can be used as Li ion-conducting electrolytes in electrochemical cells.

Why it is interesting: Because of the rapidly increasing use of phones, tablets, electric cars etc. research into improved batteries is a very hot topic. Many modern batteries use Li+-conducting seperators or ‘membranes’ with specific conductivity, solvent swelling and heat-resistance properties. According to this invention improved separator membranes can be produced from (a surprisingly simple) thermoplastic polyurethane based on (preferably) 4,4′-MDI, hydroquinone bis (hydroxyethyl)ether as chain extender and a DEG-adipic polyester diol with a MW of 2000 to 3000. Lithium conductivity can (optionally) be further improved by incorporating Li+-conducting solids like Li-Borates, Li- silicates, Li salts or complexes and the like.

Schematic Li-polymer battery.

Aqueous Polyurethane Dispersion with Integrated Nanoparticles

Title: AQUEOUS DISPERSIONS OF POLYURETHANE AND NANOPARTICLES

Number/Link: WO2013/059106

Applicant/Assignee: Bayer

Publication date: 25-04-2013

“Gist”: Amino-functional inorganic nanoparticles are reacted with residual isocyanate groups of a PUD-forming polyurethane prepolymer and subsequently dispersed in water.

Why it is interesting: A water-dispersible polyurethane prepolymer is made from isocyanate, polyol and chain extender in which polyol and/or chain extender comprise ionic or potentially ionic groups. The prepolymer is produced with a surplus of isocyanate which is subsequently reacted with amino-functional inorganic nanoparticles. The nanoparticles consist of e.g. metal oxides which were reacted with a “bridging compound” comprising an isocyanate-reactive group (NH2 or OH) and a particle-reactive group e.g. a halogen or silane group. The polyurethane with covalently integrated nanoparticles can then be dispersed in water using a known process. The resulting PUD has a high shelf-life and can be used in coatings, adhesives, films etc. with improved properties.

Polyurethane dispersion and film made from it. (Wikimedia)

Innovation in Polyurethanes

Polyurethane for Precision Lenses

Solid Polyurethane Electrolyte

Aqueous Polyurethane Dispersion with Integrated Nanoparticles

Pages

Categories

Search

Follow this blog via email

Follow Innovation in PU on Twitter